Who baptized Constantine I near the end of his life?

Constantine I was baptized near the end of his life by Eusebius of Nicomedia, the bishop of Nicomedia.12

Having long delayed the ceremony—partly due to a desire to be baptized in the Jordan River and partly due to the responsibilities of his office—Constantine fell ill while preparing for a campaign against Persia. After failing to recover at Helenopolis, he was forced to take to his bed near Nicomedia, where he received baptism and donned the white robes of a neophyte shortly before his death in 337.1